Final Answer:
The newly synthesized protein made in the ribosomes of the endoplasmic reticulum (ER) undergoes processing, folding, and modification within the ER before being transported to its final destination, often through vesicular transport.
Step-by-step explanation:
After translation on the ribosomes of the rough endoplasmic reticulum (RER), the nascent polypeptide chain enters the lumen of the ER. In the ER, the protein undergoes post-translational modifications, including glycosylation and disulfide bond formation. Chaperone proteins assist in proper protein folding to achieve its functional three-dimensional structure. Quality control mechanisms in the ER ensure that only correctly folded proteins proceed. The properly processed protein is then transported to its destination, typically the Golgi apparatus, via vesicular transport. In the Golgi, additional modifications may occur, and the protein is sorted for delivery to specific cellular compartments, secretion, or incorporation into the plasma membrane.